次のSQLクエリがエラーを返すのはなぜですか?
SELECT COUNT (DISTINCT rm.id)
FROM ts_room rm
LEFT JOIN ts_roomfacilities rf
ON rm.id = rf.room_id
LEFT JOIN ts_facilities f
ON f.id = rf.facilities_id
LEFT JOIN ts_building b
ON rm.building_id=b.id;
一見論理的に見えます!
これが私のSQLFiddleです-http : //sqlfiddle.com/#!2/a59fc/20